Malthusian growth model explained

A Malthusian growth model, sometimes called a simple exponential growth model, is essentially exponential growth based on the idea of the function being proportional to the speed to which the function grows. The model is named after Thomas Robert Malthus, who wrote An Essay on the Principle of Population (1798), one of the earliest and most influential books on population.[1]

Malthusian models have the following form:

P(t)=

rt
P
0e

where

The model can also be written in the form of a differential equation:

dP
dt

=rP

with initial condition:P(0)= P0

This model is often referred to as the exponential law.[5] It is widely regarded in the field of population ecology as the first principle of population dynamics,[6] with Malthus as the founder. The exponential law is therefore also sometimes referred to as the Malthusian Law.[7] By now, it is a widely accepted view to analogize Malthusian growth in Ecology to Newton's First Law of uniform motion in physics.[8]

Malthus wrote that all life forms, including humans, have a propensity to exponential population growth when resources are abundant but that actual growth is limited by available resources:

A model of population growth bounded by resource limitations was developed by Pierre Francois Verhulst in 1838, after he had read Malthus' essay. Verhulst named the model a logistic function.

See also

External links

Notes and References

  1. "Malthus, An Essay on the Principle of Population: Library of Economics"
  2. Book: Fisher, Ronald Aylmer, Sir, 1890-1962.. The genetical theory of natural selection. 1999. Oxford University Press. 0-19-850440-3. A complete variorum. Oxford. 45308589.
  3. Book: Lotka, Alfred J. (Alfred James), 1880-1949.. Analytical theory of biological populations. 978-1-4757-9176-1. New York. 861705456. 2013-06-29.
  4. Book: Lotka, Alfred J.. Théorie analytique des associations biologiques. 1934. Hermann. 614057604.
  5. Turchin, P. "Complex population dynamics: a theoretical/empirical synthesis" Princeton online
  6. 10.1034/j.1600-0706.2001.11310.x. Does population ecology have general laws?. Oikos. 94. 17–26. 2001. Turchin. Peter.
  7. Paul Haemig, "Laws of Population Ecology", 2005
  8. Ginzburg. Lev R.. The theory of population dynamics: I. Back to first principles. Journal of Theoretical Biology. en. 122. 4. 385–399. 10.1016/s0022-5193(86)80180-1. 1986. 1986JThBi.122..385G .